3. Results and discussion
Fig. 1. (a) and -(b) Unipolar resistive switching behavior during successive set and reset cycles for the studied Ni/HfO2-based RRAM devices with IC = 100 μA, and their corresponding (c) and -(d) double logarithmic plots.Figure optionsDownload full-size imageDownload as PowerPoint slide
In Fig. 1 it Resiquimod is also observed that the low resistive state (LRS) does not show linear conduction, a result that agrees with a recently published work , where the on-state current (Ion) was modeled by tunneling-based conduction considering the quantum point contact (QPC) theory for atomic-sized constrictions . In these constrictions, the first quantized sub-band behaves as a potential barrier for the transit of electrons  and . The different slopes in the double logarithmic plots of Fig. 1 indicate different CF configurations and different dominant contributions to the current .
Notice that the Ion/Ioff ratio is larger for negative polarity than for positive polarity for voltages lower than V = 0.5 V.